<template>
  <el-container>
    <el-header>
      <div>
        <img src="../assets/logo2.png" alt="">
        <span>电商后台管理系统</span>
      </div>
      <el-button type = 'info' @click = 'logout'>退出登录</el-button>
    </el-header>
    <el-container>
      <el-aside :width="AsideWidth">
        <div class="toggle-button" @click = "toggleCollapse">
          |||
        </div>
        <el-menu background-color="#333744" text-color="#fff" active-text-color="#409EFF" :unique-opened="true" :collapse = "isCollapse" :collapse-transition = "false" :router="true" :default-active="activePath">
          <!-- 一级菜单 -->
          <el-submenu :index="item.id + ''" v-for = 'item in menulist' :key = 'item.id'>
            <template slot="title">
              <!-- 一级菜单模板 -->
              <!-- 图标 -->
              <i :class="iconsObj[item.id]"></i>
              <!-- 文本 -->
              <span>{{item.authName}}</span>
            </template>
            <!-- 二级菜单 -->
            <el-menu-item :index="'/'+subItem.path" v-for = 'subItem in item.children' :key = 'subItem.id' @click = "saveNavState('/'+subItem.path)">
              <template>
                <i class="el-icon-menu"></i>
                <!-- 文本 -->
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      <el-main>
        <router-view />
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
  data () {
    return {
      menulist: [],
      iconsObj: {
        125: 'iconfont icon-user',
        103: 'iconfont icon-tijikongjian',
        101: 'iconfont icon-shangpin',
        102: 'iconfont icon-danju',
        145: 'iconfont icon-baobiao'
      },
      isCollapse: false,
      AsideWidth: '200px',
      // 被激活的链接地址
      activePath: ''
    }
  },
  created () {
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  // 退出登录
  methods: {
    logout () {
      // 清除session中的token值
      window.sessionStorage.clear()
      // 重定向回到登录页
      this.$router.push('/login')
    },
    async getMenuList () {
      const { data: res } = await this.$http.get('menus')
      if (res.meta.status !== 200) {
        return this.$message.error(res.meta.msg)
      }
      this.menulist = res.data
    },
    // 点击按钮切换菜单的折叠与展开
    toggleCollapse () {
      this.isCollapse = !this.isCollapse
      if (this.isCollapse === true) {
        this.AsideWidth = '64px'
      } else {
        this.AsideWidth = '200px'
      }
    },
    // 保存链接激活状态
    saveNavState (activePath) {
      window.sessionStorage.setItem('activePath', activePath)
      this.activePath = activePath
    }
  }
}
</script>
<style scoped>
.el-header{
  background-color: #373D41;
  display: flex;
  justify-content: space-between;
  padding-left: 0;
  align-items: center;
  color: white;
  font-size: 20px;
}
.el-header div{
  display: flex;
  align-items: center;
}
.el-header div span{
  margin-left: 15px;
}
.el-aside{
  background-color: #333744;
}
.el-main{
  background-color: #eaedf1;
}
.el-container{
  width: 100%;
  height: 100%;
}
img{
  height: 60px;
}
.iconfont{
  margin: 10px;
}
.el-menu{
  border-right: none;
}
.toggle-button{
  background-color: #4A5064;
  font-size: 10px;
  line-height: 24px;
  color: #fff;
  text-align: center;
  letter-spacing: 0.2em;
  cursor: pointer;
}
</style>
